Kurnianingsih Yoanna A, Mullette-Gillman O'Dhaniel A
Department of Psychology, National University of Singapore Singapore, Singapore.
Department of Psychology, National University of SingaporeSingapore, Singapore; Neuroscience and Behavioral Disorders Program, Duke-NUS Medical SchoolSingapore, Singapore; Singapore Institute for Neurotechnology (SINAPSE), National University of SingaporeSingapore, Singapore.
Front Neurosci. 2016 Nov 9;10:507. doi: 10.3389/fnins.2016.00507. eCollection 2016.
When deciding, we aim to choose the "best" possible outcome. This is not just selection of the option that is the most numerous or physically largest, as options are translated from objective value (count) to subjective value (worth or utility). We localized the neural instantiation of the value-to-utility transformation to the dorsal anterior midcingulate cortex (daMCC), with independent replication. The daMCC encodes the context-specific information necessary to convert from count to worth. This encoding is not simply a representation of utility or preference, but the interaction of the two. Specifically, the relationship of brain activation to value is dependent on individual preference, with both positive and negative slopes across the population depending on whether each individual's preference results in enhancement or diminishment of the valuation. For a given value, across participants, enhanced daMCC activation corresponds to diminished subjective valuation, deactivation to enhanced subjective valuation, and non-modulated activation with non-modulated subjective valuation. Further, functional connectivity analyses identified brain regions (positive connectivity with the inferior frontal gyrus and negative connectivity with the nucleus accumbens) through which contextual information may be integrated into the daMCC and allow for outputs to modulate valuation signals. All analyses were replicated through an independent within-study replication, with initial testing in the gains domain and replication in the intermixed and mirrored losses trials. We also present and discuss an ancillary finding: we were unable to identify parametric value signals for losses through whole-brain analyses, and ROI analyses of the vmPFC presented non-modulation across loss value levels. These results identify the neural locus of the value-to-utility transformation, and provide a specific computational function for the daMCC in the production of subjective valuation through the integration of value, context, and preferences.
在做决策时,我们旨在选择可能的“最佳”结果。这并非仅仅是选择数量最多或物理尺寸最大的选项,因为选项是从客观价值(数量)转换为主观价值(价值或效用)的。我们将价值到效用转换的神经实例定位到背侧前扣带回中部皮质(daMCC),并进行了独立重复验证。daMCC编码了从数量转换为价值所需的特定情境信息。这种编码并非简单地表示效用或偏好,而是两者的相互作用。具体而言,大脑激活与价值的关系取决于个体偏好,总体上正负斜率取决于每个个体的偏好是导致估值增强还是减弱。对于给定的价值,在参与者中,增强的daMCC激活对应于主观估值的减弱,去激活对应于主观估值的增强,而未调制的激活对应于未调制的主观估值。此外,功能连接分析确定了大脑区域(与额下回呈正连接,与伏隔核呈负连接),通过这些区域,情境信息可被整合到daMCC中,并允许输出调节估值信号。所有分析都通过独立的研究内重复进行了验证,初始测试在收益领域,重复验证在混合和镜像损失试验中。我们还展示并讨论了一个辅助发现:通过全脑分析,我们无法识别损失的参数化价值信号,并且vmPFC的ROI分析显示在损失价值水平上没有调制。这些结果确定了价值到效用转换的神经位点,并为daMCC在通过整合价值、情境和偏好产生主观估值方面提供了特定的计算功能。